Analysis of Dynamic Discharge Characteristics of Plasma Jet Based on Voltage and Current Measurements Using a Metal Plate

We present here the analysis of the dynamic discharge characteristics of the plasma jet, where we set the metal plate in the downstream region and measure its voltage and current induced by the plasma-jet contact. The voltage of the metal plate is as high as 1.9 kV at a distance of 15 mm from the plasma source under the high discharge voltage condition of 9 kV. The metal-plate voltage measured at a distance of 40 mm from the plasma source decreases markedly to 0.5 kV, which is still high enough for causing chemical reactions induced by accelerated ions in the potential. The metal-plate voltage also changes in the wide range of 0.3-1.9 kV with various discharge-voltage conditions, where the metal plate is set to a distance of 20 mm from the plasma source. Our experiments demonstrate that the voltage and current measurements using the metal plate could be used as one of the effective protocols to evaluate the plasma-jet irradiation condition in the plasma-jet process.